Process for producing separators



106. COMPOSITIONS,

UN IEQ 3 l'ollrawing. ,npplicaflunilled December To all *wkom'it mag concern. Beit known thatI, Cmnms J. a'citizen -of the United States, and'a reel- .1. dent of New Y'ox'ik city, in. the countyofhlew 8 York and 'State of New York, have invented new and usefiil Im rovements JD Processes for Producing parators, which the-following is. a specification. The invention relates 1;) a processf: for 1m- 10 re tin or I t pores. o porous ls ishi'czli iii' ei to be used asseparator members, such as diaphragms, difi'usion walls or like structures. invention has a referencezmore especially to a process for providing. separator members of a semi-permeable character, particularly suited for use in separating two liquids from each other as in an electrolytic cell and similar apparatus These vimpregnated.members afford a nonporous, more or less solid and-homogeneous separator, partition or wall, serving to preveniglfor all practical purposes, any trans mission of. fluids through them, but allowing the ions of fluids to migrate or difiuse -freely therethrough to carry the electricity and effect the desired-decompositions or combinations at theelectrodes; Y The particular. material to be im-preg- 5 nated, or its size or shape, forms no part of consist of any suitable porous substance which will form a proper skeleton, framework or. container. .Fore xa:mple, I-have found as a patricularly suitable-material oxid. materials, compose o granu ar aggregates having more or less uniform interstices, are admirably suited for the purpose, and are generally preferable to those composed of fibrous or cellular materials. However wood asbestos and various other materials may be employed to provide a suitable skeleton, frame-work or'wall to retain the impre ting material.

Heretofore, it has been the ractice, in impregnating materials for t e purpose stated, to perform the process in two steps the first consisting in saturating the porous materials as by soaking in an a ueous solution of a salt of a metal which is ca able of forming a gelatinous or colloids, hydrate. The second step consisted in immers- 65 ing the thus treated material in a solution of a suitable precipitating agent, as a by the present invention, and said 'material may- .filtros, which is composed of ains o sand or cr stalline silica, also, alundum will is composed of granular aluminum wmsrcnnn; or 2031:, n. Y. I

I l. momsroa raonuonmammrons;

" jj.,s,emsaa oflevberslatenu Patented Oct. 11., 1921.

1a,.1s1s. Serial 10.266535. 4 g drate- .In other cases, the material was first saturated with a solu 'mg a] icate, and, secondly, immersed in d' ute sulfuric acid or;v other acid to cause a precipitation ofgelatinoussilic nu,

l n iu- '0 1 etho s of producing separator members in manner similar to those hereinbefore recited are more particularly set forth in a co-pendmg application Serial No. 16285, filed by-me the 22nd dayof :March, 1915.

if" v i I have found, however, that a much more satisfactory imation may be afforded by the process reinafter described and claimed, particularly in that the impregnatingmaterial be-uniformly distributed and the-impregnation effected more 000- nomically and expeditiously. In the processes heretofore practised, diffusion of the precipitat l1 uid into the dlap ra a- 7 5 ter al was retar e an e inous material more or less unequally distri ute ue to the immediate filling of the surface interstices and pores with the said.,g'elationous material. 1. f

, In accordance -with the present invention,

instead of the successive operations hereinbefore noted, that is'to say, first saturating with a suitable hydrate-forming or similar material and thereupon .immersing in a precipitating orvcoagulating-i-liquid to fix the gelatinous medium in the members, a liquid mixture, which doesnot immediatel c l et1n1ze,1s'previoti; ly prepa-rdd and may con-' 51 ,1' or example, of sodium silicate and an acid. The materia e impregnated is lien saturated in this combined solution. It is to be understood, of course, -that'suitable proportions and conditions are to, be maintained. For example, a quantity of the sodium silicate solution is prepared of one part of 40 B. sodium silicate solution and two parts of water, and this is poured into an equal quantity of previously diluted and cooled sulfuric acid made of 66 B. sulfuric acid diluted with two parts of water. rtaln precautions should be observed in the mim'ng of these two solutions to prevent the immediate setting or lumping of silica hiydrate. To this end, the sodium silicate so ution is best poured' in a thin stream into the dilute sulfuric acid with rapid stirring, the resulting mixture being, when first prepared, a substantially limpid 1i uid of uniform consistency.

nto the liquid mixture or hydrosol thus prepared, which Waiter an member this 're are or othe maral the diaphragm-member, i

:theacnblmmaterialinxeliqnid mixture 0 sodium elatinizes or therein, or it may; ppe crew at mtenvalsjn til glhtiii'iisi"" $ithin said material after silicate and sulfuric or other acid, said mixtime a5 the silica hydrate p roger sets iii-4m appreciable apse of time. the se a ato uc urey e same wi m "t e ruc ure a transparent, homo; feneous and uniformly fiistrihuted, ie'llyike, electrolytically conductiye mass. I Under-thjeaforesaid conditions, some twe nty to thirty minutes will be required or the liquid to" roperly set or gelatinize. is lled with a an I I n u neous. 10D 'ran'sm'ittin mewhlch is 11m orm y is n u '0 rmly ra'tame an W ll 0- I emrs impregn hereinbefore set forth will be of substantially uniform ,eondrQivi tymgsmuch' as theione will migrate 'freely gnd'u iformly throu h allof thehomogeneously filledioids'l Said members, moreover;

I fie more readily Q an'd rapidly produced iu thiimainnerj an'd with", minimum cost and waste of materiali The excess sulfuric 7 acid and the-"salts suoh as sodium sulfate; ma be retainedor 'i'emov'ed, as'gdesired. lFurt er: more, to maintainfthe' diaphragm in a moisteuedcondition,should it be removed from the electrolyte iu whichjit'islusedysuliuric acid 'or other -hygrosejopic" substeinces' fmay bereiutroduoed, as "'is' wen understood-"l1,

I claim; v v 7 a f 1 The method I of producing Ia separator membe'rfwhich c'onsits'in immersin a suitable material in'afliquid mixture 0 asuh staiioe capable of-forming a gelatinous "me dium and 'a'eoagulant therefor, said mixture gel'atiriizing within said material aftermi appreciable lapse 1052 time; j Q

-2. The method of produclng 'a' separato memberywhich consiste'in immersin a suitable'material'ir 'aliquid mixture 0 ,sodium silieat'e' and a coagulant therefor, said mix; ture' glatinizing within said material after an :appreciablelapse of time] 33 ee. The method f producing eeparatdr k -The method of producing =11?llepsirator' member, ghich in immersiu a,suitable material'in "a li ind mixturewi Hil'ufed a .7 euclng a separator member, which consists ill-JIDIHBISIIlg a suitable materiel 'iuamiziture composed of-equal v uantitiesiof asohition of one part of 40 sodium silicate and two. arts of water and of 66913 'sulful'iiigid eluted with-two '16, The metho of rbili infg A seiimiai member,"wliicli' cousists in im'mersin for approximately one-half houfr a suitab e mate if'ie i iq d m xtu sbdium si at arid a" "coagulant therefor, eaid mixture gewithin'said' materialiafter ape pigs i ehpse ewm ing aquanti ofia soliitiomconsi'tip fgf one pm o 1 w ne'- isn cae "ss u and tw -d s. fi fii e ifi ap d stir aud inasuitabl stream,i nt am ualjquantity of 66 Bhsul' furiq acid ute with-two p I: g r I? {by r a f SignedfatNeWYdrkfm the, unty 6f New Yorkahd State of Sew" York 6fDeoembef''A'. 1). 191 .13 a e i 

